Effect of seed rate on vegetative growth and yield properties of two varieties of spinach and weeds

Sonia Hiwa Othman, Bakhtyar Abdulla Hamasaaid , Soran Othman Abdulla
Department of Horticulture, Faculty of Agricultural Sciences, University of Sulaimani, Kurdistan Region, Iraq.
Department of Plant Protection, Directorate of Research Center in Sulaimani.


An experiment was conducted at the Agricultural Research Station in Bakrajo- Sulaimaniyah, from 7th October, 2013 to 24th March, 2014 to investigate the effect of different seed rates (16, 28, 40 Kg ha-1) on a number of weeds m-2 and their dry weight. Furthermore, some vegetative and yield characters of two spinach varieties (local and Syrian) were measured. The experiment designated in factorial randomized complete block design (RCBD-factorial). Comparisons between the means of the characters were carried out according to Duncan’s Multiple Range Test at the 5 % level. Results revealed that 40kg ha-1 exhibited significant differences in reducing thenumber and dry weight of weeds at both growth stages [100 and 125 days after spinach seed sowing (DAS)] by 67.86 and 75.82% for weed’s number and for weed’s dry weight (67.57 and 48.27%) as compared to 16 kg ha-1. Also 40 kg ha-1 was significantly superior in increasing accumulative yield (kg m-2), Dry weight (g m-2), leaf area (cm2 plant-1),spinach number m-2and leaf number plant-1 by60.91, 66.56, 57.33, 47.93 and 28.88% ascompared to 16 kg ha-1, respectively. The local variety got the highest values in decreasing the number and dry weight of weeds at both growth stages 100 and 125DAS by 43.94 and 51.76% for weed’s number and by 19.46 and 30.49% for weed’s dry weight, compared to the Syrian variety, respectively. The local variety showed significant differences, as compared to Syrian variety, in accumulative yield (kg m-2), dry weight (g m-2), leaf area (cm2 plant-1), spinach number m-2 and leaf number plant-1 by 49.40, 47.06, 38.64, 30.97 and 21.86%, respectively. To sum up, seeding rate of 40 kg ha-1 was best in reducing the number and dry weight of weeds, and it caused significant increases in all studied parameters.

Key Words:
Seed rate Weed, Spinach Local variety Syrian variety.


[1] Prince Edward Islands (PEI) Department of Agriculture, Fisheries and Aquaculture. Atlantic Provinces Vegetable Crops Guide to Pest Management. Publication No. 1400A. (2005).

[2] Avsar, B. “Genetic diversity of Turkish spinach cultivars (Spinacea oleracea L.)” a master dissertation, graduate school of Engineering and Sciences, Izmir Institute of Technology, Turkey. (2011).

[3] Citak, S. and Sonmez, S. “ Mineral contents of organically and conventionally grown spinach (Spinacea oleracea L.) during two successive seasons” J. Agric. Food Chem. 57: 7892-7898. (2009).

[4] Hedges, L.J. and Lister, C.E.”Nutritional attributes of spinach, silver beet and eggplant” New Zealand Institute for Crop & Food Research Limited Private Bag 4704, Christchurch, New Zealand. (2007).

[5] FAO “Statistical database” Food and Agricultural Organization of the United Nations, Rome, Italy. (2014).

[6] LeStrange, M.; Koike, S. J.; Valencia, and Chaney, W. E. “Spinach Production in California” Available online: vric.ucdavis.edu/richome/html/veginfo/commodity/spinach/spinachprod.html. (1999).

[7] Takele, E. “Spinach production”: Sample costs and profitability analysis. University of California. Agriculture and Natural Resources. Publication No. 8032. (1999).

[8] Peruzzi, A.; Ginanni, M.; Raffaelli, M. and Borelli, M. “Physical weed control in organic spinach production” 6th EWRS Workshop on Physical and Cultural Weed Control 15. Lillehammer, Norway, 8-10 March 2004.(2004).

[9] Fennimore, S. A. ; Smith, R. F. and Mcgiffen, Jr. M. E. “ Weed Management in Fresh Market Spinach (Spinacia oleracea) with S-metolachlor” Weed Technology. 15: 511–516. (2001).

[10] Kristiansen, P. E. “ Sustainable weed management in organic herb and vegetable production”: A thesis of Doctor. University of New England. (2003).

[11] Henderson, C.W.L. and Bishop, A.C. “ Vegetable weed management systems” In: Sindel, B.M., ed. Australian Weed Management Systems. R.G. and F.J. Richardson, Melbourne. pp. 355-372. (2000).

[12] Alexandria, L. “ Understanding seeding rates recommended planting rates and pure live seed” United States department of agriculture, plant material Technical Note. No. 11.(2009).

[13] Kathleen D. ; Petersen, T. S. and freelance “Weed Management for Organic Farmer” Iowa state university, university extension. PM, 1883. (2002)

[14] Finney, D. M. and Creamer, N. G. “ Weed Management on Organic Farms” North Carolina cooperative extension service. College of agriculture and life science. (2008).

[15] Djurovka, M.; Lazic B. and Markovic, V. “ General characters of spinach varieties suitable for industrial processing” ISHS Acta Horticulturae 220 (1): International Symposium on Vegetables for Processing. (1987). (Abstract only).

[16] Xinping, C.; Chunqin, Z.; Yaping, L. and Fusuo, Z. “ The nitrate content difference and the reason among four spinach varieties” Plant natrition and fertilizen science, 1, 004. (2000). (Abstract only).

[17] Drovnic, C.E.; Howel, G. S. l and Elore, A. J. “ Influence of crop load on photosynthesis and dry matter partitioning at several grape vines” Seasonal change in single leaf and whole vine photosynthesis. Amer. J. End. Vitic. 46(40): 469-477. (1965).

[18] Al-Rawi, K. M. and Khalafullah, A. A. M. “Design and analysis of agricultural experiments” Dar Al-Kutub press. University of Mosul. (1980).